布林线开口开始扩大选股公式。公式模块 N:=20;BOLL:=MA(CLOSE,N);UB:=BOLL+2*STD(CLOSE,N);LB:=BOLL-2*STD(CLOSE,N);KK:=UB/LB;CROSS(KK>REF(KK,1),0.5);